1. Field of the Invention
The invention relates in general to transportation apparatus for moving people between spaced landings, such as electric stairways and movable walks, and more specifically to the handrails and drive therefor, of such apparatus.
2. Description of the Prior Art
Transportation devices for the movement of passengers between spaced points or landings, such as electric stairways and walks, employ endless flexible handrails which are driven in synchronism with the conveyor portion of the device. The handrails are supported by balustrades which direct the handrails above the conveyor on which the passengers stand during the load run. The drives for the handrails are normally applied thereto during the return run of the handrails.
The handrail drive commonly employs a plurality of spaced pairs of rollers, with the handrail passing between the rollers of each pair. Each pair of rollers includes a driven traction roller and a pressure roller, with the pressure roller being resiliently biased towards its associated traction roller.
Handrail drive arrangements of the prior art are illustrated in U.S. Pat. Nos. 3,414,109 and 3,779,360 which are assigned to the same assignee of the present application. As illustrated in these patents, the traction roller includes a metallic hub portion, commonly a machined casting, upon which an elastomeric or rubber tire is mounted. While this prior art traction roller construction functions satisfactorily, it adds substantially to the cost and weight of the handrail drive unit. Thus, it would be desirable to reduce the manufacturing cost, and weight of the traction rollers, if these objectives can be achieved without deleteriously affecting the performance and service life of traction rollers.